Insulated electrode holder



Dec. 10, 1946. M. WELLS I 9 INSULATED ELECTRODE HOLDER Filed July 12, 1944 INVENTOR.

MA RTIN we L 5 BY 7 ATTORNEY Patented Dec. 10, 1946 UNITED STATES PATENT OFFICE 11 Claims.

My invention relates to a holder for a metal rod or electrode employed in electric welding processes, and is a continuation-in-part of my copending application for Electrode holder, Serial No. 487,681, filed May 20, 1943.

It is an object of the invention to provide a completely insulated electrode holder which is of slender form and light weight and is so constructed that parts thereof which are subjected to severe wear may be readily placed without the use of tools.

It is an object of the invention to provide an electrode holder having a handle from which there projects a relatively slender substantially cylindric metal body equipped with means to grip an electrode or welding rod, this metal body having thereon a separate insulator which may be readily placed in operative position by the mere expedient of sliding it into place, there being means operative between the body and the insulator engaging to hold the insulator in place on the body.

It is an object of the invention to provide an electrode holder of the class described having a replaceable tubular insulator reeniorced by metal reenforcing means therein, and having means for engagement with the head or body of the electrode holder so as to hold the insulator in place. This insulator is subjected to heavy service, and should it become injured or broken,

may be readily replaced by a new, duplicate, insulator without loss of time and without need for tools or tool-operated fastening means.

It is a further object of the invention to provide an electrode holder wherein one of the jaws for gripping the electrode comprises a portion of the metal body of the holder, and the other jaw member comprises a rod arranged to move axially, this electrode holder having for use on the forwardly extended portion thereof a cap formed A from insulating material, and a further object of the invention is to provide on the interior of such cap a resiliently disposed latch means for holding the cap in operative position on the holder.

A further object of the invention is to provide a simple replacement insulator which may be readily applied to the electrode holder, and a further object of the invention is to provide an insulator of this character having a tubular wall to enclose a portion of the electrode holder, there being a relatively small opening in this tubular wall leading in from the end of the tubular wall in substantially parallel relation to the axis thereoflpnewall of this small opening being formed by or comprising a latch means which is secured within the insulator during the process of molding the same.

A further object of the invention is to provide a cooperation of electrode holder with a tubular insulator which by reason of the insulator fitting loosely upon the metal body of the holder, movement is provided therebetween to break loose materials which tend to accumulate in the joint between the electrode holder body and the insulator where the rod opening extends through these parts, thereby minimizing arcing at this point.

Further objects and advantages of the invention will be brought out in the following part of the specification.

Referring to the drawing which is for illustrative purposes only,

Fig. 1 is a partly sectioned side view of an electrode holder embodying my invention.

Fig. 2 is a cross section to enlarged scale taken as indicated by the line'2-2 of Fig. 1.

Fig. 3 is an elevational view of the reticulated reenforcing element of the insulator shown in Fig. 1.

Fig. 4 is a fragmentary sectional view taken as indicated by the line 44 of Fig. 1.

Fig. 5 is a fragmentary sectional view taken as indicated by the line 55 of Fig. 1.

Fig. 6 is a perspective view of the spring finger employed in the insulator.

In Fig. 1 I show an electrode holder comprising a handle ll! of insulating material and a head H. The head It includes a metal body l2 of approximately cylindric form having a rounded front end 13. This head H has near its front end a lateral opening M to receive a portion of a welding electrode 25. The head I! has an axial opening it which extends from the inner portion of the lateral opening M to the rear end of the head H. A portion of this axial opening [6 is defined by threads ii to receive the threaded portion 18 of a rod or bar is, the forward end of which is adapted to engage the welding electrode l5 and the rearward portion of which provides a means whereby an electric conductor may be connected to the body H2, in the known manner followed in the art. The rearward portion 20 of the bar member it] extends from the rear end of the body l2 and is connected to the handle l0 so that by rotation of the handle it), the member I 3 may be caused to rotate and through threaded engagement with the body l2, advance toward or recede from the inner end of the weld-- ing electrode 15. The body I2 has thereon a;

' part.

is slidable thereonto from the front end of the body I2. This insulator is molded from a durable insulatin compound such as Bakelite and has therein a reenforcing element 2'! which is of metal and is embedded in the material of the insulator 25 during the molding thereof. The reenforcing element 21 is of recticulated character so as to provide many openings through which the insulating material passes.

A feature of my invention is that .1 form this reticulated reenforcing element 21 from woven mesh screen 30, as shown in Fig. 3. A strip of the screen is turned back upon itself intermediate its ends and the transverse wires 3! of the screen 30 are bent to semicircular form, thereby producing of the screen 351 a reenfo-rcing element 27 defining a hollow cylinder having the rounded front end 32 to correspond to and lie within the rounded front end wall 26 of the insulator 25. As clearly shown in Fig. 2, the

insulator 25 has therein a longitudinal channel 33 providing shoulder means St to engage the rib or shoulder 22 of the body 52, so that the insulator 25 will not rotate on the body [2. Along a portion of the channel 33, the insulator 25 internally carries a spring finger 36 which is adapted to engage the transverse shoulder 24 of the body [2 when the insulator 25 is slid into position on the body l2, thereby providing a means of engagement between the body i2 and the insulator 25 to hold the insulator 25 in position on the body 12. It will be understood that this insulator 25 may be supplied to the user of the electrode holder as a replacement The spring finger 38 has at its rear end, as shown in Fig. 6, tongues 31 which are embedded in the wall of the insulator 25 during the process of molding the insulator. As shown in Fig. 1, an opening 39 extends into the wall of the insulator 25 from the rear end face, one

of the walls or margins of this opening 39comprising the spring finger 35. The opening 39 lies behind the spring finger 36 and into this opening 39 an instrument may be inserted to bend the front end of the spring finger into the cavity of the insulator 25 so that it will be in a position for engagement with the shoulder 24 when the insulator 25 is placed on the body I2. During the molding of the insulator 25, the opening 39 is occupied by a metal bar or pin which assists in maintaining the spring finger 36 in its desired position.

It will be noted that the insulator 25 has an opening 40 aligned with the opening it of the head ll, through which the electrode l5 passes. In the use of the device particles of metallic or electro-conductive material pass into and through the opening 40, and the heat encountered in the use of the device may char the wall of the opening 40 so that it is somewhat carbonized. A special feature of my present invention, which I believe constitutes a valuable contribution to the electrode art, consists in the provision of means for preventing bridging of electroconductive materials between the insulator 25 and the head II at the openings [4 and 50.

It will be noted that there is a space 4| between the insulator 25 and the head ll so that the insulator 25 is movable on the head H a sufficient distance to break down any accumulations of bridging material between the adjacent portions of the openings [4 and 46. This substantially avoids the destruction of the end of the metal head i l which has occurred in insulated electrode holders having the tubular insulator fixed rigidly on the metal body.

I claim as my invention:

1. In an insulating means for an electrode holder having a metal body having a rod opening leading in from a face thereof to meet an internal openin in said body, said body having a locking shoulder thereon, means in said internal opening to grip a rod in said rod opening, a handle for supporting said body, and means for connecting an electric conductor to said body, the combination of: a tubular insulator having an opening to receive said body and being slidable onto said body, and having therein a resilient finger to engage said locking shoulder so as to prevent removal of said insulator from said body, said insulator having a small opening leading in from its end, one wall of said small opening being formed by said finger.

2. In an insulating means for an electrode holder having a metal body having a rod opening leading in from a face thereof to meet an internal opening in said body, said body having a wall formed so as to provide a shoulder thereon, means in said internal opening to grip a rod in said rod opening, a handle for supporting said body, and means for connecting an electric conductor to said body, the combination of: a tubular insulator slidable onto said body, said tubular insulator having therein a resilient catch means to engage said shoulder so as to prevent removal of said insulator from said body.

3. In an electrode holder of the class described, the combination of: a handle; rod holding means carried by said handle comprising actuating means and a part to engage and cooperate in the holding of a rod; an insulator for said part, said part and said insulator bein so cooperatively formed for interengagement that said insulator may he slid onto said part into operative position relatively thereto and embodying a tubular wall to surround said part; and resiliently disposed catch means operative between said part and said insulator to hold sai insulator in place on said part.

lpln an electrode holder of the class described, the combination of: a handle; rod holding means carried by said handle comprising actuating means and a part to engage and cooperate in the holding of a rod, said part having an external locking shoulder; an insulator for said part, said part and said insulator being so cooperatively formed for interengagement that said insulator may be slid onto said part into operative position relatively theretoyand a resiliently disposed finger connected to said insulator contiguous to its inner face, so that it will be positioned between said insulator and said part, to engage said locking shoulder and hold said insulator in place on said part.

5. In an insulator means for an electrode holder of the class described having a handle, rod holding means carried by said handle comprising actuating means and a part to engage and cooperate in the holding of a rod, the combination of: an insulator for said part, said part and said insulator being so cooperatively formedfor interengagement that said insulator may be slid onto said part into'operative position relatively thereto; and resiliently disposed catch means operative between said part and said insulator to hold said insulator in place on said part.

6. In an insulator means for an electrode holder of the class described having a handle, rod holding means carried by said handle comprising actuating means and a part to engage and cooperate in the holding of a rod, said part having an external locking shoulder, the combination of: an insulator for said part, said part.

and said insulator being so cooperatively formed for interengagement that said insulator may be slid onto said part into operative position relatively thereto; and a resiliently disposed finger connected to said insulator contiguous to its inner face, so thatit will be positioned between said insulator and said part, to engage said locking shoulder and hold said insulator in place on said part.

7. In an insulating means for an electrode holder having a metal body having a rod Opening leading in from a face thereof to meet an internal opening in said body, said body having a transverse shoulder thereon, means in said internal opening to grip a rod in said rod opening, a handle for supporting said body, and means for connecting an electric conductor to said body, the combination of: a tubular insulator slidable onto said body, said tubular insulator having therein a resilient catch means to engage said transverse shoulder so as to prevent removal of said insulator from said body, said insulator being loosely fitted on said body so that there will be such free relative movement between said insulator and said body as to prevent the formation of a bridge of conductive material between said body and said insulator.

8. In an electrode holder of the class described, the combination of a handle; rod holding means carried by said handle comprising actuating means and a part to engage and cooperate in the holding of a rod; an insulator for said part, said part and said insulator being so cooperatively formed for interengagement that said insulator may be slid onto said part into operative position relatively thereto, said insulator being loosely fitted on said body so that there Lil 6. will be relative movement between said insulator and said body to prevent the formation of a bridge of conductive material between said body and said insulator; and resiliently disposed catch means operative between said part and said insulator to hold said insulator in place on said part.

9. In an electrode holder of the class described, the combination of: a handle; rod holding means carried by said handle comprising actuating means and a part to engage and cooperate in the holding of a rod; an insulator for said part, said part and said insulator being so cooperatively formed for interengagement that said insulator may be slid onto said part into operative position relatively thereto, said insulator being loosely fitted on said body so that there will be relative movement between said insulator and said body to prevent the formation of a bridge of conductive material between said body and said insulator; and means operative between said part and said insulator to hold said insulator in place on said part.

10. In an electrode holder of the class described, the combination of a handle; rod holding means carried by said handle comprising actuating means and a part to engage and cooperate in the holding of a rod; an insulator for said part; and means for holding said insulator on said part so that it will be loose upon said part for the purpose of preventing the formation of electroconductive material between the part and the insulator.

11. In an insulating means for an electrode holder having a metal body having a rod opening leading in from a face thereof to meet an internal opening in said body, said body having a transverse shoulder thereon, means in said internal opening to grip a rod in said rod opening, a handle for supporting said body, and means for connecting an electric conductor to said body, the combination of: a tubular insulator slidable onto said body, the opening in said tubular member being of such size that said tubular member will have loose relative movement on said body to prevent accumulation of electroconductive materials between said tubular member and said body.

MARTIN WELLS. 

